Ab initio study of polarons in the alkali halides

ORAL

Abstract

A charge carrier propagating through a crystal induces distortions in the lattice via the electron-phonon interaction. The quasiparticle formed by the carrier and the lattice distortion is referred to as a polaron. Recent advances have enabled the calculation of small and large polarons on the same footing from first principles [Phys. Rev. Lett. 122, 246403 (2019); Phys. Rev. Lett. 129, 076402 (2022)]. In this talk, we present a systematic application of these methods to a broad family of materials that span a very wide range of electron-phonon interaction strengths, the alkali halides. We show that these compounds consistently host large electron polarons and small hole polarons. By investigating how the coupling mechanism, formation energy, and polaron radius depend on materials properties such as dielectric constants, band gaps, and effective masses, we establish general scaling laws and we identify the validity range of standard polaron models.

*This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award DE-SC0020129. Computational resources were provided by the Texas Advanced Computing Center (TACC) at The University of Texas at Austin, the National Energy Research Scientific Computing Center (a DOE Office of Science User Facility supported under Contract No. DE-AC02-05CH11231), and the Argonne Leadership Computing Facility (a DOE Office of Science User Facility supported under Contract DE-AC02-06CH11357).

–

Presenters

  • Chao Lian

    • University of Texas at Austin
    • The University of Texas at Austin

Authors

  • Chao Lian

    • University of Texas at Austin
    • The University of Texas at Austin

  • Jon Lafuente-Bartolome

    • The University of Texas at Austin
    • University of Texas at Austin

  • Weng Hong Sio

    • University of Macau

  • Feliciano Giustino

    • University of Texas
    • University of Texas at Austin
    • The University of Texas at Austin